New York: fifty years ago, Yankee Stadium had about 70,000 seats. It seldom sold out, and almost any kid could afford the cheapest seats. Capacity was reduced to about 57,000 when the stadium was remodeled in the 1970s. Most games sell out now, and prices have gone up.

The new stadium, opening next year, will reduce seating to about 51,800. This intentional contraction is aimed at guaranteeing sellouts, increasing demand, allowing the owners, in short order, to triple prices or more. The owners have learned that scarcity will fatten their wallets. The plan may discriminate against the lower middle class, but as long as the owner is footing the bill without public subsidies, there may be little grounds for complaint.

Now fossil-fuel moguls are intent on hoodwinking the entire planet with an analogous scheme.

The basic trick is oil producers overstating fossil-fuel reserves. Government “energy information” departments parrot industry. Partly because of disinformation, the major efforts needed to develop alternative energies have not been made.

The reality of limited supply forces prices higher. Eventually, sales volume will begin to decline, but fossil-fuel moguls will make more money than ever. They’ll continue to assert that there’s plenty more oil, gas or coal to be found, aiming to keep the suckers on the hook. Indeed, they may find somewhat more in the deep ocean, under national parks, in polar regions, offshore, and in other environmentally sensitive areas. They don’t need much to keep the suckers paying higher and higher prices.

Oil “reserves” suddenly doubled when Organization for the Petroleum Exporting Countries decided that production quotas would be proportional to official reserves. These higher reserves are, at least in part, phantom. Coal “reserves” are based on estimates made many decades ago. Closer study shows that extractable coal reserves are vastly overstated, consistent with present production difficulties and rising prices. The presumed 200-year supply of coal in the United States is a myth, but it serves industry moguls well.

Conventional fossil-fuel supplies are limited, even if we tear up the Earth to extract every last drop of oil and shard of coal. Tearing up the Earth to get at those last drops - Exxon/Mobil proudly advertises that they’re drilling the depths of the ocean and searching the most extreme pristine environments - is as insane as the smoker who trudged four miles through a raging storm to buy a pack of Camel cigarettes to feed his nicotine addiction.

It would be possible to find more fossil fuels, and extend our addiction and pollution of the environment, should we be so foolish as to take the path of extracting unconventional fossil fuels such as tar shale and tar sands on a large scale. That choice cannot be left to the discretion of industry moguls. The planet does not belong to them.

Our conclusion is that, if humanity wishes to preserve a planet similar to the one on which civilisation developed and to which life on Earth is adapted, CO2 must be reduced from its present 385ppm (parts per million) to, at most, 350ppm. We find that peak CO2 can be kept to about 425ppm, with large estimates for oil and gas reserves, if coal use is phased out by 2030 (except where CO2 is captured and sequestered) and unconventional fossil fuels are not tapped substantially. Peak CO2 can be kept close to 400ppm, if actual reserves are closer to those estimated by “peakists”, who believe that the globe is already at peak global oil production, having extracted about half of readily extractable oil resources.

This lower 400ppm peak can be ensured, assuming phase-out of coal emissions by 2030, if a practical limit on reserves is achieved by means of actions that prevent fossil-fuel extraction from public lands, off-shore regions under government control, environmentally pristine regions and extreme environments. The concerned public can influence this matter, but time is short, the industry voice is strong and climate effects have not yet become so obvious to the public as to overwhelm the disinformation from industry moguls.

A near-term moratorium on coal-fired power plants and constraints on oil extraction in extreme environments are essential, because once CO2 is emitted to the air much of it will remain there for centuries. Improved agricultural and forestry practices, mostly reforestation, could draw down atmospheric CO2 by about 50ppm by the end of the century. But a greater drawdown by such more-or-less natural methods seems impractical, making a long-term overshoot of the 350ppm target level, with potentially disastrous consequences, a near certainty if the world stays on its business-as-usual course.

If we choose a different path, which permits the possibility of achieving 350ppm CO2 or lower this century, we can minimise the chance of passing tipping points that spiral out of control, such as disintegration of ice sheets, rapid sea level rise and extermination of countless species. At the same time, we could solve problems that seem intractable, such as acidification of the ocean with consequent loss of coral reefs.

In any event, we must move beyond fossil fuels soon, because a large fraction of CO2 emissions will linger in the atmosphere for many centuries.

The world must move to zero fossil-fuel emissions. This is a fact, a certainty. So why not do it sooner, in time to avert climate crises? At the same time, we halt other pollution that comes from fossil fuels, including mercury pollution, conventional air pollution, problems stemming from mountain-top removal and more.

Breaking an addiction is not easy. But we may be like the smoker who trudged four miles through rain to get a pack of Camels - when he got back to his motel he threw the pack away and never smoked again.

Fossil-fuel addiction is more difficult - one person’s epiphany cannot solve the problem. This problem requires global co-operation. We must be on a new path within the next several years, or reducing CO2 levels this century becomes implausible. Developed countries, the source of most excess CO2 in the air today, must lead in developing clean energy and halting emissions. Yet it is hardly a sacrifice: “Green” jobs will be an economic stimulus and a boon to worker well-being.

A major fight is brewing - it might be called war. On the one side, we find the short-term financial interests of the fossil-fuel industry. On the other side: young people and other beings who will inherit the planet. The fight seems uneven. The fossil-fuel industry is launching a disinformation campaign, and they have powerful influence in capitals around the world.

Young people seem pretty puny in comparison to industry moguls, and animals don’t talk or vote. The battle may start with local and regional skirmishes, one coal plant at a time. But it could build rapidly - we’re running out of time.

Meanwhile, the moguls’ dirtiest trick is spewing “green” messages to the public - propaganda, intended to leave the impression they’re moving in the right direction. Meanwhile they hire scientific has-beens to dispute evidence and confuse the public.

When will we know that the long-term public interest has overcome the greed? When investors, companies and governments begin to invest en masse in renewable energies, when all aim for zero-carbon emissions.

James Hansen is director of the NASA Goddard Institute for Space Studies and Adjunct Professor at the Columbia University Earth Institute.